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    <p>While @Konrad Rudolph's answered your specific question, I'd like to continue where he left off saying: </p> <blockquote> <p>This makes no sense and shouldn’t even compile (or at least give a warning). Your first code is fine – it works always and there is no downside. It’s not clear what the second code is even trying to achieve.</p> </blockquote> <p>He's right in that you shouldn't even be doing what your second line is suggesting. The simple answer that achieves the effect you are trying for, would be to use <code>TryCast</code> instead. You are only assigning a non-empty string value when <code>drTest("column")</code> contains a value. Since that's the case, why not do:</p> <pre><code>Dim sTest As String = TryCast(drTest("column"), String)</code></pre> <p>This way you get your value if the <code>TryCast</code> succeeds, otherwise you get <code>Nothing</code>.</p> <p>Now since <code>TryCast</code> returns <code>Nothing</code> and since your example showed that you wanted to assign <code>""</code>, you might not want to go this route, as it can lead into the frustration of handling String Nothingness vs "" / String.Empty. You could use the <code>String.IsNullOrEmpty()</code> method if you want, but that requires you to pass in your string as a parameter and, to me, that clunks up your code. Alternatively, you could create your own StringExtensions Module like I have and use the extensions to check Nothingness and Emptiness:</p> <pre><code>Option Explicit On Option Strict On Imports System.Runtime.CompilerServices Public Module StringExtensions &lt;Extension()> _ Public Function IsNullOrEmpty(ByVal s As String) As Boolean Return s Is Nothing OrElse s.Trim.Length.Equals(0) End Function &lt;Extension()> _ Public Function IsNotNullOrEmpty(ByVal s As String) As Boolean Return s IsNot Nothing AndAlso s.Trim.Length > 0 End Function End Module</code></pre> <p>Then to achieve your effect of setting <code>""</code> with respect to Nothingness, one could use the combination of the <code>TryCast</code> and my StringExtensions methods to do:</p> <p><strong>With ternary If</strong></p> <pre><code>Dim sColumn1 As String = TryCast(drTest("column1"), String) Dim sColumn2 As String = TryCast(drTest("column2"), String) Dim sColumn3 As String = TryCast(drTest("column3"), String) Dim sTest1 As String = If(sColumn1.IsNotNullOrEmpty, sColumn1, String.Empty) Dim sTest2 As String = If(sColumn2.IsNotNullOrEmpty, sColumn2, String.Empty) Dim sTest3 As String = If(sColumn3.IsNotNullOrEmpty, sColumn3, String.Empty)</code></pre> <p><strong>Without ternary If</strong></p> <pre><code>Dim sTest1 As String = String.Empty Dim sTest2 As String = String.Empty Dim sTest3 As String = String.Empty Dim sColumn1 As String = TryCast(drTest("column1"), String) Dim sColumn2 As String = TryCast(drTest("column2"), String) Dim sColumn3 As String = TryCast(drTest("column3"), String) If sColumn1.IsNotNullOrEmpty Then sTest1 = sColumn1 If sColumn2.IsNotNullOrEmpty Then sTest2 = sColumn2 If sColumn3.IsNotNullOrEmpty Then sTest3 = sColumn3</code></pre>
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    1. POIs this similar to the ternary operator in vb.net?
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